TecEco Gaia Engineering Technologies

A very short summary of TecEc Gaia Engineering technologies is included in this section. For more detail of Greensols and other technologies that are part of Gaia Engineering go to the relevant sections of the Gaia Engineering web site.

A Graphic Depicting the Gaia Engineering Process

The Gaia Engineeringtececology embraces a number of new technologies including TecEco’s Tec-Kiln technology for emission free calcination and the production of concrete using our Tec, Eco and Enviro-Cements, a carbon dioxide scrubbing technology, heat capture and transfer technologies and carbonation/desalination technologies that can profitably deliver massive sequestration and waste utilisation.

The TecEco Cement System

TecEco Cements comprise a
blending system of hydraulic cements such as ordinary Portland Cement and reactive
magnesia[1] and usually also a pozzolan and
were invented in response to technical problems exhibited by Portland Cement
and the need for more sustainable binders. The range of new technically superior binders that have been developed include Tec, Eco and Enviro-cements.

Tec-Cements (5 -20% MgO, 80 – 95% PC) contain more Portland Cement than reactive magnesia[1]. Reactive magnesia[1] hydrates in the same rate order as Portland Cement forming Brucite which uses up water reducing the voids:paste ratio, increasing density and possibly raising the short term pH. Reactions with pozzolans are more affective and we recommend the removal of lime (which is far to mobile and reactive to be left in a durable binder) in this manner. After all the Portlandite has been consumed Brucite and CSH control the long term pH which is lower
and due to its low solubility, mobility and reactivity results in greater durability. Other benefits include improvements in density, strength and rheology, reduced permeability and shrinkage and the use of a wider range of aggregates many of which are potentially wastes without reaction problems.

Enviro-Cements (20-95% MgO, 80-5% PC) contain similar ratios of MgO and PC
to Eco-Cements but in non permeable concretes brucite does not carbonate readily.
Higher proportions of magnesia[1] are most
suited to toxic and hazardous waste immobilization and when durability is required.
Strength is not developed quickly nor to the same extent.

Technical issues addressed by the new TecEco Cement technology include:

Durability

Sulphate and chloride resistance

Carbonation

Corrosion of steel and other reinforcing

Delayed reactions (e.g. alkali aggregate and delayed ettringite)

Freeze-thaw

Rheology

Workability, time for and method of placing and finishing, stick and rebound
with mortars.

Dimensional change including shrinkage

Cracking, crack control

Bonding to brick and tiles

Waste immobilization and utilization

Efflorescence

Concretes are already a relatively sustainable material. With low cost high
thermal capacity they supply essential thermal mass to buildings. With the advent
of TecEco technology, concretes will offer greater opportunities for sustainability
with other improved properties such as:

Full details of the TecEco Tec-Kiln technology have not been released to the public domain due to patent issues.

We can say however that the kiln is designed to operate using non fossil fuel energy and involves a controlled pressure closed system in which calcining
and grinding occur at the same time and in which gases such as CO2 released
are captured.

The distribution of reactivity of the output is minimized and reactivity easily
controlled. Specific surface areas of over 150m2.gm-1 should not be difficult
to achieve.

Parties interested in the development of this technology please contact TecEco.

[1] Reactive magnesia is also variously
known as caustic calcined magnesia, caustic magnesia or CCM. The temperature of firing has a greater influence on reactivity than grind size as excess energy goes into lattice energy.